The present invention relates to a method for preventing, in a fluid storage tank which requires temperature control, a liquid cooling or heating medium that flows and circulates in an enclosed pressure-resistant jacket provided around an outer wall of said fluid storage tank from entering into said fluid storage tank during breakage failure of the wall of said storage tank, as well as a plant therefore.
A storage tank for storing a large amount of materials has come to be used in accordance with development of industrialization of manufacturing of various products. It is generalized to monitor (control) or maintain the temperature in the tank in compliance with the properties and use of the fluid stored in the tank. A conventional plant which monitors (controls) or maintains the temperature in a fluid storage tank 22 as shown in FIG. 9 can be generally accomplished by allowing a liquid cooling or heating medium to flow in an enclosed pressure-resistant jacket 24 provided around an outer wall of the fluid storage tank by means of a pressurization pump 27 and returning it to a cooling or heating medium-storage tank 23. The temperature of the cooling or heating medium in said cooling or heating medium-storage tank 23 is regulated by a temperature control unit 28.
However, according to a conventional method and plant in which a cooling or heating medium is forced to flow in an enclosed pressure-resistant jacket provided around an outer wall of a fluid storage tank by means of a pressurization pump to monitor (controls) or maintain the temperature of a fluid in the fluid storage tank, there were defects that the cooling or heating medium enters into the storage tank, thereby contaminating the fluid in the tank with the medium in an event that small breakage failures such as cracks, pinholes or the like generated at the wall of the tank. In addition, if the breakage failures such as cracks, pinholes or the like are very small, they cannot be visually confirmed and thus it was not possible to know contamination of the fluid in the tank. It was considered to be probable that products having a problem with regard to quality came into market.